Fighting the rise of the superbug

Discovery of a new antibiotic resistant gene by Cardiff University researchers changes global attitude and policy to monitoring and prevention.

The World Health Orgnisation lists the problem of antibiotic resistance as one of the
greatest threats that humanity faces in the 21st century.

In the UK alone,
some 5,000 people a year die from infections that are resistant to
antibiotics. Drug resistance is steadily
growing, reducing the effectiveness of our most powerful antibiotics.

The issue lies with
bacterial enzymes called beta-lactamases which are able to break down
antibiotics such as penicillin. A
sub-group of these enzymes – carbapenemases - break down the most clinically
useful group of these antibiotics – carbapenems. The most potent of these bacterial enzymes
are metallo- beta-lactamases (MBL) for which there are no known clinical
inhibitors.

A contaminated country

In 2008, Professor
Timothy Walsh and Dr Mark Toleman from Cardiff University discovered a
new MBL - New Delhi Metallo-beta-lactamase (NDM-1) - which has spread globally
more rapidly than any other type of antibiotic resistance.

In collaboration
with Channel 4 journalists, the pair discovered that the environment of India
was significantly contaminated with the NDM-1 bacteria. Their work changed the global understanding
of antibiotic resistance. Some of their
key findings on NDM-1 were that:

it was widespread in the Southern Asian community, not just hospitals, making it a very different type of antibiotic resistance

it possesses a unique genetic structure, context and origin

it has been exceptional in spreading through diverse bacterial species

the rapid spread was assisted by overseas travel and surgery.

Walsh and Toleman
were responsible for 90% of the molecular characterisation of NDM-1 as well as
being the first to report it being present in key human pathogens.

World Health Orgnisation (WHO)

WHO is the directing and coordinating authority for health within the
United Nations system. It is responsible for providing leadership on
global health matters, shaping the health research agenda, setting norms
and standards, articulating evidence-based policy options, providing
technical support to countries and monitoring and assessing health
trends.

Tackling the infection

In November
2009, Walsh and Toleman were part of a UK-wide Department of Health call,
alerting all UK hospitals and departments to this new type of antibiotic
resistance. Their NDM-1 studies were
used to ensure mandatory screening was conducted on all patients arriving from
overseas hospitals. Europe, South Africa
and Canada also enhanced and upgraded their infection control measures.

In India, direct responses to Walsh and Toleman's research were underway. In 2010, a
National Task Force produced India's first ever national antibiotic
policy. Two years later, all major Indian
clinical, academic and research bodies met to discuss the implementing of
antibiotic stewardship, infection control and national surveillance. This led to the government taking the
issue of antibiotic resistance more seriously. As NDM-1 was
prevalent in the water system, they issued chlorine tablets to
those inhabitants of New Delhi who are unable to afford bottled water.

Public
awareness and the seriousness of 'superbugs' was significantly increased
following the publication of Walsh and Toleman's ground-breaking paper in Lancet Infectious Diseases. This article on NDM-1 was the fourth biggest
television news story worldwide, with the story hitting the front pages of the
main broadsheet newspapers in the UK.

The
international interest generated by Walsh and Toleman's research led to them giving over 50
international talks on NDM-1, addressing the European Parliament with the Head of WHO,
presenting to NATO surgeons and gaining membership on the World Health Associated
infection forum.